<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title>参考链接：https://codepen.io/abxlfazl/pen/VwKzaEm</title>
		<!-- https://dribbble.com/shots/5619509-Animated-Tab-Bar -->
	</head>
	<style>
		html {

			box-sizing: border-box;
			--bgColorMenu: #1d1d27;
			--duration: .7s;

		}

		html *,
		html *::before,
		html *::after {

			box-sizing: inherit;

		}

		body {

			margin: 0;
			display: flex;
			height: 100vh;
			overflow: hidden;
			align-items: center;
			justify-content: center;
			background-color: #ffb457;
			-webkit-tap-highlight-color: transparent;
			transition: background-color var(--duration);

		}

		.menu {

			margin: 0;
			display: flex;
			/* Works well with 100% width  */
			width: 32.05em;
			font-size: 1.5em;
			padding: 0 2.85em;
			position: relative;
			align-items: center;
			justify-content: center;
			background-color: var(--bgColorMenu);

		}

		.menu__item {

			all: unset;
			flex-grow: 1;
			z-index: 100;
			display: flex;
			cursor: pointer;
			position: relative;
			border-radius: 50%;
			align-items: center;
			will-change: transform;
			justify-content: center;
			padding: 0.55em 0 0.85em;
			transition: transform var(--timeOut, var(--duration));

		}

		.menu__item::before {

			content: "";
			z-index: -1;
			width: 4.2em;
			height: 4.2em;
			border-radius: 50%;
			position: absolute;
			transform: scale(0);
			transition: background-color var(--duration), transform var(--duration);

		}


		.menu__item.active {

			transform: translate3d(0, -.8em, 0);

		}

		.menu__item.active::before {

			transform: scale(1);
			background-color: var(--bgColorItem);

		}

		.icon {

			width: 2.6em;
			height: 2.6em;
			stroke: white;
			fill: transparent;
			stroke-width: 1pt;
			stroke-miterlimit: 10;
			stroke-linecap: round;
			stroke-linejoin: round;
			stroke-dasharray: 400;

		}

		.menu__item.active .icon {

			animation: strok 1.5s reverse;

		}

		@keyframes strok {

			100% {

				stroke-dashoffset: 400;

			}

		}

		.menu__border {

			left: 0;
			bottom: 99%;
			width: 10.9em;
			height: 2.4em;
			position: absolute;
			clip-path: url(#menu);
			will-change: transform;
			background-color: var(--bgColorMenu);
			transition: transform var(--timeOut, var(--duration));

		}

		.svg-container {

			width: 0;
			height: 0;
		}


		@media screen and (max-width: 50em) {
			.menu {
				font-size: .8em;
			}
		}
	</style>
	<body>
		<menu class="menu">

			<button class="menu__item active" style="--bgColorItem: #ff8c00;">
				<svg class="icon" viewBox="0 0 24 24">
					<path d="M3.8,6.6h16.4" />
					<path d="M20.2,12.1H3.8" />
					<path d="M3.8,17.5h16.4" />
				</svg>
			</button>

			<button class="menu__item" style="--bgColorItem: #f54888;">
				<svg class="icon" viewBox="0 0 24 24">
					<path d="M6.7,4.8h10.7c0.3,0,0.6,0.2,0.7,0.5l2.8,7.3c0,0.1,0,0.2,0,0.3v5.6c0,0.4-0.4,0.8-0.8,0.8H3.8
		        C3.4,19.3,3,19,3,18.5v-5.6c0-0.1,0-0.2,0.1-0.3L6,5.3C6.1,5,6.4,4.8,6.7,4.8z" />
					<path d="M3.4,12.9H8l1.6,2.8h4.9l1.5-2.8h4.6" />
				</svg>
			</button>

			<button class="menu__item" style="--bgColorItem: #4343f5;">
				<svg class="icon" viewBox="0 0 24 24">
					<path d="M3.4,11.9l8.8,4.4l8.4-4.4" />
					<path d="M3.4,16.2l8.8,4.5l8.4-4.5" />
					<path d="M3.7,7.8l8.6-4.5l8,4.5l-8,4.3L3.7,7.8z" />
			</button>

			<button class="menu__item" style="--bgColorItem: #e0b115;">
				<svg class="icon" viewBox="0 0 24 24">
					<path d="M5.1,3.9h13.9c0.6,0,1.2,0.5,1.2,1.2v13.9c0,0.6-0.5,1.2-1.2,1.2H5.1c-0.6,0-1.2-0.5-1.2-1.2V5.1
		          C3.9,4.4,4.4,3.9,5.1,3.9z" />
					<path d="M4.2,9.3h15.6" />
					<path d="M9.1,9.5v10.3" />
			</button>

			<button class="menu__item" style="--bgColorItem:#65ddb7;">
				<svg class="icon" viewBox="0 0 24 24">
					<path d="M5.1,3.9h13.9c0.6,0,1.2,0.5,1.2,1.2v13.9c0,0.6-0.5,1.2-1.2,1.2H5.1c-0.6,0-1.2-0.5-1.2-1.2V5.1
		          C3.9,4.4,4.4,3.9,5.1,3.9z" />
					<path d="M5.5,20l9.9-9.9l4.7,4.7" />
					<path
						d="M10.4,8.8c0,0.9-0.7,1.6-1.6,1.6c-0.9,0-1.6-0.7-1.6-1.6C7.3,8,8,7.3,8.9,7.3C9.7,7.3,10.4,8,10.4,8.8z" />
				</svg>
			</button>

			<div class="menu__border"></div>

		</menu>

		<div class="svg-container">
			<svg viewBox="0 0 202.9 45.5">
				<clipPath id="menu" clipPathUnits="objectBoundingBox"
					transform="scale(0.0049285362247413 0.021978021978022)">
					<path d="M6.7,45.5c5.7,0.1,14.1-0.4,23.3-4c5.7-2.3,9.9-5,18.1-10.5c10.7-7.1,11.8-9.2,20.6-14.3c5-2.9,9.2-5.2,15.2-7
		          c7.1-2.1,13.3-2.3,17.6-2.1c4.2-0.2,10.5,0.1,17.6,2.1c6.1,1.8,10.2,4.1,15.2,7c8.8,5,9.9,7.1,20.6,14.3c8.3,5.5,12.4,8.2,18.1,10.5
		          c9.2,3.6,17.6,4.2,23.3,4H6.7z" />
				</clipPath>
			</svg>
		</div>
	</body>
	<script>
		"use strict";

		const body = document.body;
		const bgColorsBody = ["#ffb457", "#ff96bd", "#9999fb", "#ffe797", "#cffff1"];
		const menu = body.querySelector(".menu");
		const menuItems = menu.querySelectorAll(".menu__item");
		const menuBorder = menu.querySelector(".menu__border");
		let activeItem = menu.querySelector(".active");

		function clickItem(item, index) {

			menu.style.removeProperty("--timeOut");

			if (activeItem == item) return;

			if (activeItem) {
				activeItem.classList.remove("active");
			}


			item.classList.add("active");
			body.style.backgroundColor = bgColorsBody[index];
			activeItem = item;
			offsetMenuBorder(activeItem, menuBorder);


		}

		function offsetMenuBorder(element, menuBorder) {

			const offsetActiveItem = element.getBoundingClientRect();
			const left = Math.floor(offsetActiveItem.left - menu.offsetLeft - (menuBorder.offsetWidth - offsetActiveItem
				.width) / 2) + "px";
			menuBorder.style.transform = `translate3d(${left}, 0 , 0)`;

		}

		offsetMenuBorder(activeItem, menuBorder);

		menuItems.forEach((item, index) => {

			item.addEventListener("click", () => clickItem(item, index));

		})

		window.addEventListener("resize", () => {
			offsetMenuBorder(activeItem, menuBorder);
			menu.style.setProperty("--timeOut", "none");
		});
	</script>
</html>
